It might seem like common sense to test DNA evidence from sexual assaults to help catch more criminals, but a bill that would make that mandatory is getting some fierce opposition from the State Sheriff's Association.

It's the subject of a hearing tomorrow in Sacramento. Last year, the I-Team uncovered thousands of untested sexual assault evidence kits sitting on police property room shelves across the Bay Area. After that, a state lawmaker introduced a bill to fix the problem and it passed the Assembly by a vote of 79-0. But, the opposition is not going away without a fight.

The California State Sheriff's Association is coming out strongly against the rape kit bill. Stanislaus County Sheriff Adam Christianson is the group's president, and he says, "The problematic part of this piece of legislation is really the unfunded mandate and the over-burdensome regulation that it brings. Really this is about local control. It's about the sheriffs having the discretion in determining which forensic cases we refer to the Department of Justice."

Assm. Nancy Skinner, D-Berkeley, sponsored the measure to test all rape kits. She said, "Any profession likes to have discretion and we, we recognize that, but we think in this particular incident, their body is the crime scene. So, that means that they need to be at a doctor's office or a hospital, have that evidence basically, you know, through a medical examination collected. It deserves to at least get into the national database."

The Skinner bill does not include new funding for the tests that can run $800 or more a piece, but she argues it's worth it. Cities which test all sexual assault evidence have seen a dramatic increase in the number of cases solved.

"This would be sort of these pie in the sky discussions if we didn't know that it works," Skinner says. "Because, for example, in New York City, when New York City tested its entire backlog at the point that they tested it was a 17,000 backlog. Their rape arrest record went up to 70 percent."

In response to opposition from the sheriffs and the Lab Directors Association, Skinner amended the bill:

Law enforcement would have had five days to submit a rape kit to a crime lab. Skinner changed that to 10.

She also doubled the number of days that labs would have to upload a DNA profile to the national database to 60.

The bill would not go into effect until Jan. 1, 2016.

Christianson says, "It's a step in the right direction, but it's not enough."

The sheriffs want more concessions, including full funding of the additional workload for crime labs, or they want the bill pulled.

Christianson argues, "We think we can get the job done and support our victims and serve the people and protect people without the unnecessary regulatory mandates."

Skinner says the state budget is in better shape now, so funding may be easier to obtain. And the federal government has pledged $41 million to reduce the backlog of untested rape kits across the country.